Research news

African elephants are often considered to represent a single species, Loxodonta africana, which is distinct from the Asian elephant genus Elephas. In the August 24 Science, Alfred Roca and colleagues from the US National Cancer Institute challenge this assumption by presenting their results of a phylogenetic analysis
of African elephants (Science 2001, 293:1473-1477). They collected dart-biopsy samples from almost two hundred free-ranging
elephants from 21 populations and sequenced 1732 nucleotides from four nuclear genes. Phylogenetic analysis of these sequences demonstrated that African elephants can
be divided into distinct forest and savannah populations. Savannah populations were
genetically closer to each other than to any of the forest populations. The genetic
distance between forest and savannah elephants was 9.0, which corresponds to 58% of
the distance between African and Asian elephant genera. The results suggest that the
two African populations split approximately 2.63 million years ago. Roca et al. propose that African elephants should therefore be considered as two species, Loxondonta africana (savannah elephants) and Loxondonta cyclotis (forest elephants).